1. Field of the Invention
The present invention relates to a filling and sealing apparatus for filling a package having one end open and the other end closed with fluid through the open end and then sealing the latter.
2. Prior Art
Such a filling and sealing apparatus usually comprises a spout attaching device, a spout fusing device, a filling device and a sealing device.
The spout attaching device functions to temporarily attach a spout 2 on a flap of an open end portion A of a package 1 having the other end B closed, as shown in FIG. 18. In the flap of the package 1, a hole 3 is preliminarily provided for temporary attachment of the spout 2. The package 1 is formed from the so-called paper lamination material which is formed by laminating on both surfaces of a paper sheet synthetic resin films of for example, polyethylene. The spout 2 is a mold of synthetic resin such as polyethylene and has a pouring portion 4 and a flat flange 5.
The spout fusing device functions to fuse the spout 2 attached temporarily on the package 1 and adhere it to the latter. The filling device functions to fill the package 1 with drink material such as liquor or fruit juice through the open end A thereof. The sealing device functions to seal the open end A of the package 1 filled with such liquid.
Upon completion of the sealing operation of the sealing device, the package filled with liquid becomes a product, as shown in FIG. 19. The package is usually in the form of cylinder having square or rectangular cross section and the open end portion A is defined by an upper flap portion C including a pair of opposing flaps and another pair of opposing flaps which are orthogonal to the first flap pair. The flaps of the first opposing flap pair are folded to allow edge portions of the flaps of the other pair to be adhered to each other. The spout 2 is secured to one (D) of the flaps thus adhered together. Liquid filling the package 1 is poured through the spout 2.
U.S. Pat. No. 4,788,811 discloses a spout fusing device of ultrasonic type for fusing a temporarily attached spout 2 to a package. The ultrasonic fusing device is used to heat a flange 5 of the spout 2 and a portion of the package 1 which is in contact therewith, by applying ultrasonic vibration thereto to thereby fuse them together.
When this method is used, an anvil 6 is inserted into the package 1 so that the flange portion 5 of the spout 2 is held stably and a vibration horn 7 of the ultrasonic fusing device is abutted externally to the spout 2. By applying ultrasonic vibration through the ultrasonic vibration horn to the flange 5 and the package flap, the latter two are heated and fused together, as shown in FIG. 20.
When this fusing is used, however, temperature of the anvil 6 may be increased by repeated fusing operations, causing fusing conditions of the spout 2 to be changed with temperature change of the anvil 6. As a result, there is a strong possibility of unsatisfactory fusing of the spout 2. For example, when the anvil temperature becomes very high, the package 1 may be fused to the anvil 6, so that the package 1 can not be pulled out easily from the anvil 6 after the fusing operation or it can be broken if pulled out.
When atmospheric temperature of a place in which the fusing operation is being performed is too low, temperature of the anvil 6 is also too low. Therefore, an output of the ultrasonic fusing device regulated preliminarily to a desired temperature may become insufficient to heat the spout 2 to the desired temperature, as a result of which the fusing of the spout 2 becomes incomplete.
Since the pouring portion 4 of the spout 2 temporarily attached to the package 1 protrudes outwardly of the package 1, as shown in FIG. 20, the horn 7 has to have a recess 8 for receiving the protruded pouring portion with annular gap therebetween when the horn 7 is positioned to the shown place to apply ultrasonic vibration to the flange 5 of the spout 2. With the annular space provided between the recess 8 and the spout 2, the pouring portion 4 of the latter may be vibrated excessively in direction perpendicular to its axis when ultrasonic vibration is applied through the horn 7 thereto, resulting in pin holes in the spout 2.
In an example of the spout 2, there is a shield portion 9 provided integrally with the flange 5, as shown in FIG. 21. The shield portion 9 functions to prevent the liquid in the container 1 from being exposed to atmosphere and is bounded with respect to the flange 5 by an annular thin portion defined by an annular groove 10. In order to remove the shield portion 9 when the package is to be used, a pull-up ring 11 is integrally formed on the shield portion 9. That is, when it is desired to pour the liquid out from the package 1, a cap of the pouring portion 4 is removed from the flange 5 and then the pull-up ring 11 is pulled up by a finger to break the annular groove 10 to thereby separate the shield, portion 9 from the flange 5, resulting in an opening.
In such spout 2 as having the groove 10 formed in the flange, 5, when the pouring portion 4 is vibrated excessively, there may formed pin holes in, particularly, the groove portion or even there is a possibility of local breakage of the groove portion.
In order to prevent an excessive vibration of the pouring portion 4, an elastic member 12 of such as rubber is provided on a bottom of the recess 8 of the horn 7 causes to so that the pouring portion 4 is urged by the elastic member 12 to absorb excessive vibration, as shown in FIG. 22.
In such conventional device, however, since the elastic member 12 is made in intimate contact with the bottom of the recess 8, vibration of them due to ultrasonic vibration transmitted thereto by the horn 7 causes to generate frictional heat therebetween which causes an abnormally large load to be applied to the ultrasonic oscillation source driving the horn 7. Therefore, it becomes difficult to reliably perform the fusing operation of the spouts to the packages for a long period of time.
As mentioned above, in the conventional spout fusing device, there are problems of temperature change of the anvil 6, abnormal heat generation of the ultrasonic horn 7 and impossibility of reliable fusing of the spout to the package.